The present invention pertains to power tools. More particularly, the present invention pertains to retraction systems for the drive spindles of power tools.
Power tools, particularly air or electrically driven power tools, include a drive spindle. The drive spindle normally operates at high rpm and rotates a drill chuck or other device in order to perform work on a work piece. The operation of the device requires advancement of the drive spindle into the work piece. For optimum performance of work on the work piece, the drive spindle is kept at high rotation speeds.
When the work has been accomplished, it is necessary to retract the drive spindle from the work piece. The fabrication of a rapid, reliable retraction system to retract a drive spindle from a work piece has caused problems for power tool designers for many years. Some prior art systems employ a drive dog mechanism for retraction of the drive spindle from the work piece. Such drive dog systems have a tendency to jam when operated at high speeds.
There is, therefore, a need in the art to provide a rapid, reliable retraction system for drive spindles of power tools that can be operated at high speeds.